Sahih al-Bukhari 34:146
Narrated Ibn Shihab:
If somebody bought fruits before their benefit is evident and then the fruits were spoiled with blights, the loss would be suffered by the owner (not the buyer). Narrated Salim bin 'Abdullah from Ibn Umar: Allah's Messenger (ﷺ) said, "Do not sell or buy fruits before their benefit was evident and do not sell fresh fruits (dates) for dried dates."
Reference
Sahih al-Bukhari 34:146
In-book reference
Book 34, Hadith 146
Arabic Text
قَالَ اللَّيْثُ حَدَّثَنِي يُونُسُ، عَنِ ابْنِ شِهَابٍ، قَالَ لَوْ أَنَّ رَجُلاً، ابْتَاعَ ثَمَرًا قَبْلَ أَنْ يَبْدُوَ صَلاَحُهُ، ثُمَّ أَصَابَتْهُ عَاهَةٌ، كَانَ مَا أَصَابَهُ عَلَى رَبِّهِ، أَخْبَرَنِي سَالِمُ بْنُ عَبْدِ اللَّهِ عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لاَ تَتَبَايَعُوا الثَّمَرَ حَتَّى يَبْدُوَ صَلاَحُهَا، وَلاَ تَبِيعُوا الثَّمَرَ بِالتَّمْرِ ".